The present disclosure relates generally to fluid mixing valves and more particularly to thermostatic mixing valves having an improved adaptability to an inverted fluid supply configuration.
Thermostatic mixing valves can provide a source of water having a desired temperature and can maintain the desired water temperature substantially constant once set. Such devices are well known in the art. For example, U.S. Pat. Nos. 6,279,604 and 7,240,850 describe various embodiments of a thermostatic mixing valve. Typically, the desired water temperature is obtained by controlling the relative proportions of hot and cold water admitted to a mixing chamber and adjusting the relative proportions to maintain the desired water temperature substantially constant.
To control the relative proportions of hot and cold water admitted to the mixing chamber, a temperature-sensitive element can be provided. The temperature-sensitive element may expand or contract based on the temperature of the water in the mixing chamber. The temperature-sensitive element may be connected to a piston configured to variably adjust an amount of the hot or cold water permitted to enter the mixing chamber based on the state of the temperature-sensitive element.
While these thermostatic mixing valves are known in the art, these devices suffer from a number of disadvantages. For example, current thermostatic mixing valves may not operate properly unless the hot and cold water enter the valve through designated hot and cold fluid inlet ports. If the thermostatic valve is improperly connected, the temperature-sensitive element may cause the piston to open or close the wrong inlet port in response to a change in temperature.
Current solutions to this problem typically involve replumbing the hot and cold water supply lines or reinstalling the valve in an upside-down configuration such that the hot and cold water enter the valve through the proper inlet ports. However, such solutions are burdensome and may require the wall to be broken and reconstructed. There remains a need for a thermostatic mixing valve that can adapt to an inverted fluid supply line configuration.